Method for forming magnetic tunnel junction structure and method for forming magnetic random access memory using the same

A method of fabricating a magnetic tunnel junction structure, the method comprising:

• forming a magnetic tunnel junction layer by sequentially stacking a first magnetic layer, a tunnel dielectric layer, and a second magnetic layer on a substrate;
• forming a mask pattern on a region of the second magnetic layer;
• forming a magnetic tunnel junction layer pattern and a sidewall dielectric layer pattern on at least one sidewall of the magnetic tunnel junction layer pattern by performing at least one etch process and at least one oxidation process multiple times,
• the at least one etch process including a first etch process to etch a portion of the magnetic tunnel junction layer using the inert gas and the mask pattern to form a first etch product,
• the at least one oxidation process including a first oxidation process to oxidize the first etch product attached on the etched side of the magnetic tunnel junction layer,
• the at least one etch process further including a second etch process to etch a portion of the magnetic tunnel iunction layer not etched by the first etch process to form a second etch product,
• the at least one oxidation process including a second oxidation process to oxidize the second etch product formed by the second etch process,
• wherein, the at least one etch process etches a part of the magnetic tunnel junction layer pattern by using an inert gas, and the at least one oxidation process oxidizes a product created by the at least one etch process to form the sidewall dielectric layer pattern.